Folding Bed

ABSTRACT

Disclosed is a folding bed, comprising a connecting rod assembly, a folding bed frame, a thigh board, a shank board and a first driving device, thigh board is rotatably connected to shank board; connecting rod assembly comprises two first connecting rods, two second connecting rods and a first linking rod, one end of the first connecting rod is slidably connected to shank board, and another end is rotatably connected to the folding bed frame; one end of the second connecting rod is rotatably connected to the first connecting rod, another end of the second connecting rod is used for driving thigh board of the folding bed to rotate, and the two ends of first linking rod are fixedly connected to the two first connecting rods, respectively; the first driving device is used for pushing the first linking rod to drive shank board and thigh board to move.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation Application of PCT Application No. PCT/CN2020/106244 filed on Jul. 31, 2020, which claims the benefit of Chinese Patent Application No. 202020298605.4 filed on Mar. 11, 2020. All the above are hereby incorporated by reference in their entirety.

FIELD OF THE INVENTION

The present application relates to the technical field of furniture manufacturing, in particular to a folding bed.

BACKGROUND OF THE INVENTION

With the improvement of people's living standards, all kinds of furniture used in life are also more intelligent and comfortable. Electric folding beds are also widely used. By arranging a motor under a bed body to drive and control the rotation and lifting of a bed board, the shape of the bed board can be adjusted according to people's needs to adapt to people's sleeping posture.

A household folding bed on the existing market is large in size and heavy in weight, and still occupies a large area even if the folding bed is folded, thus cannot meet the user's requirement that the bed is as small and thin as possible. The design thickness of a folding bed frame is generally high, and is generally 120 mm-200 mm, and the existing folding bed is complex in structure, heavy in weight and high in transportation cost.

In the initial state of a household folding bed on the existing market, the included angle between a driving motor and a bed board is too small, so a large initial thrust is required to smoothly rotate the bed board; in order to solve the problem about the initial included angle, a driving motor and a bracket are arranged below a bed frame in a protruding manner, so the folding bed still occupies a large area even if the folding bed is folded.

SUMMARY OF INVENTION

Aiming at the deficiencies of the prior art, the objective of the present invention is to provide a folding bed, comprising a connecting rod assembly, a folding bed frame, a thigh board, a shank board and a first driving device, wherein the thigh board is rotatably connected to the shank board; the connecting rod assembly comprises two first connecting rods, two second connecting rods and a first linking rod, wherein one end of the first connecting rod is slidably connected with the shank board of the folding bed, and the other end of the first connecting rod is rotatably connected to the folding bed frame; one end of the second connecting rod is rotatably connected to the first connecting rod, the other end of the second connecting rod is used for driving the thigh board of the folding bed to rotate, and two ends of the first linking rod are fixedly connected to the two first connecting rods, respectively; the first driving device comprises a first motor and a first push rod, wherein the first motor is for driving the first push rod, and the first push rod is used for pushing the first linking rod so as to drive the shank board and the thigh board to move.

Further, a point where the second connecting rod is rotatably connected to the first connecting rod is close to the shank board side of the folding bed, and points where the first linking rod is fixed to the two first connecting rods are close to the folding bed frame side.

Further, the folding bed further comprises a first guide rail, wherein the first guide rail is fixedly connected to the back face of the shank board, and is provided with a first guide slot which is a linear slot.

Further, the folding bed further comprises a first sliding piece, wherein the first sliding piece is connected to one end of the first connecting rod and can slide in the extension direction of the first guide slot.

Further, the overall thickness of the connecting rod assembly after the connecting rod assembly is folded is less than the frame thickness of the folding bed frame, and the frame thickness of the folding bed frame is less than 85 mm.

Further, the first driving device further comprises a first connecting piece, wherein one end of the first connecting piece is rotatably connected to the first push rod, and the other end of the first connecting piece is connected to the first linking rod.

Further, the inner side frame of the folding bed frame is rotatably connected to the first connecting rod by means of an assembly, the assembly comprises a hollow sleeve and a screw, the hollow sleeve is fixedly connected to the folding bed frame, the first connecting rod hollowly sleeves the hollow sleeve, and the screw is in matched connection to the hollow sleeve.

Further, an end of the thigh board close to the shank board is provided with a linkage piece, one end of the linkage piece is rotatably connected to the second connecting rod, and the other end of the linkage piece is fixedly connected to the thigh board.

Further, the folding bed further comprises a seat board and a back board, wherein the folding bed frame comprises a back frame and a leg frame that are hinged to each other, the back board is arranged on the back frame, and the seat board, the thigh board and the shank board are hinged in sequence and arranged on the leg frame; a hinge assembly and a second driving device are arranged between the back board and the back frame, and the second driving device drives the back board to rotate relative to the back frame via the hinge assembly.

Further, the hinge assembly comprises a second linking rod and two back brackets, wherein one end of the back bracket is slidably connected to the back board of the folding bed, the other end of the back bracket is rotatably connected to the folding bed frame, two ends of the second linking rod are fixedly connected to the two back brackets, respectively, and the second linking rod is connected to the second driving device and drives the back board to rotate relative to the folding bed frame.

Further, points where the second linking rod is connected to the two back brackets are close to the folding bed frame side.

Further, the hinge assembly further comprises a second guide rail, wherein the second guide rail is fixedly connected to the back face of the back board, and is provided with a second guide slot which is a linear slot.

Further, the hinge assembly further comprises a second sliding piece, wherein the second sliding piece is connected to one end of the back bracket and can slide in the extension direction of the second guide slot.

Further, the overall thickness of the hinge assembly after the hinge assembly is folded is less than the frame thickness of the folding bed frame, and the frame thickness of the folding bed frame is less than 85 mm.

Further, the folding bed further comprises a second driving device, wherein the second driving device comprises a second motor and a second push rod, the second motor is fixed to the folding bed frame and is used for driving the second push rod, the second push rod is used for pushing the second linking rod so as to drive the back board to rotate relative to the folding bed frame.

Further, a second connecting piece is arranged between the second push rod and the second linking rod, one end of the second connecting piece is rotatably connected to the second push rod, and the other end of the second connecting piece is connected to the 1 second linking rod.

Further, the inner side frame of the folding bed frame is rotatably connected to the back bracket by means of an assembly, the assembly comprises a hollow sleeve and a screw, the hollow sleeve is fixedly connected to the folding bed frame, the back bracket hollowly sleeves the hollow sleeve, and the screw is in matched connection to the hollow sleeve.

Further, the back board comprises a first back board and a second back board that are hinged to each other, wherein the first back board is slidably connected to the back bracket, and the second back board is fixed to an end of the back frame close to the leg frame.

The technical solution of the present invention has at least the following advantages and beneficial effects:

(1) both the connecting rod assembly and the hinge assembly of the folding bed of the present invention can be fully folded in the bed frame to better meet requirements of consumers on the folding appearance, at the same time, the folding bed can be used on the ground with zero clearance, and the connecting rod assembly of the folding bed is simple in structure and can enable the overall thickness of the bed frame to be reduced from 120-200 mm in the prior art to less than 85 mm;

(2) the structure of the folding bed of the present invention is simplified while the strength and functionality of the folding bed are ensured, and the folding bed occupies less area compared to the prior art after being folded, so that the transportation cost is greatly reduced;

(3) the connecting rod assembly is additionally provided with the second connecting rods, so that the shortcoming of the inadequate support structures of the existing folding bed is solved, the structural strength of the folding bed is greatly enhanced, and the service life of the folding bed is prolonged; and

(4) due to the arrangement of the hinge assembly of the folding bed, the initial included angle between the motor and the push rod on the back and the back board in the initial state is increased, so that the initial thrust required to adjust the rotation of the back board is reduced, and the back brackets and second linking rod form an I-like structure, thereby increasing the stability of the back board when the back board is unfolded.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as a limitation to the scope. Those of ordinary skill in the art may obtain other related drawings from these drawings without any creative effort.

FIG. 1 is a structural schematic diagram of a connecting rod assembly of a folding bed;

FIG. 2 is a schematic diagram of a shank board and a thigh board of a folding bed being folded relative to a folding bed frame;

FIG. 3 is an exploded structural schematic diagram of an assembly and a first connecting rod of a folding bed that are assembled;

FIG. 4 is a structural schematic front view of a folding bed in an unfolded state;

FIG. 5 is a structural schematic diagram of a hinge assembly of a folding bed;

FIG. 6 is a detail schematic diagram of a partial structure of a hinge assembly of a folding bed;

FIG. 7 is a schematic diagram of fixing positions of metal pieces of a folding bed;

FIG. 8 is a schematic diagram of positions of metal pieces and supporting pieces of a folding bed; and

FIG. 9 is a schematic diagram of a folding bed in an initial state.

Reference signs: 1-connecting rod assembly, 11-first connecting rod, 12-second connecting rod, 13-first linking rod, 14-first guide rail, 141-first guide slot, 15-first sliding piece, 151-rolling wheel, 152-fastener, 16-first reinforcing rib, 2-folding bed frame, 21-shank board, 22-thigh board, 23-seat board, 24-back board, 241-first back board, 242-second back board, 25-back frame, 26-leg frame, 3-first driving device, 31-first motor, 32-first push rod, 33-first connecting piece, 34-second reinforcing rib, 4-assembly, 41-hollow sleeve, 42-screw, 43-fixing piece, 44-washer, 5-linkage piece, 6-hinge assembly, 61-back bracket, 62-second linking rod, 63-second guide rail, 631-second guide slot, 64-second sliding piece, 7-second driving device, 71-second motor, 72-second push rod, 73-second connecting piece, 8-metal piece, 9-supporting piece.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work fall within the protection scope of the present invention.

“one embodiment” or “an embodiment” described herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms “upper”, “lower”, etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, but is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. In addition, the terms “first” and “second” are only used for the purpose of description, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined with “first” or “second” may expressly or implicitly include one or more of that feature. Also, the terms “first”, “second”, etc. are used to distinguish similar objects, and are not necessarily used to describe a specific order or precedence. It should be understood that the data so used is interchangeable under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in sequences other than those illustrated or described herein.

It should be noted that when one component is described to be “fixed to” the other component, it is possible that the component is directly fixed to the other component or a component exists between the component and the other component. When one component is considered to be “connected to” the other component, it is possible that the component is directly connected to the other component or a component exists between the component and the other component. When one component is considered to be “arranged on” the other component, it is possible that the component is directly arranged on the other component or a component exists between the component and the other component.

In embodiments of the present invention, during use, the side where the head of a person is located is defined as the head of the folding bed, and the side where the foot of the person is located is defined as the foot of the folding bed, and during use, the face that the person is in contact with the bed board is defined as the upper surface of the bed board, and the other face is defined as the back face, that is, the lower surface.

EMBODIMENT

FIGS. 1-3 show a connecting rod assembly for a folding bed of the present application. The connecting rod assembly comprises two first connecting rods 11, two second connecting rods 12 and a first linking rod 13, wherein one end of the first connecting rod 11 is slidably connected to a shank board 21 of the folding bed, and the other end of the first connecting rod 11 is hinged with a folding bed frame 2; one end of the second connecting rod 12 is rotatably connected to the first connecting rod 11, the other end of the second connecting rod 12 is used for driving a thigh board 22 of the folding bed to rotate, and the two ends of the first linking rod 13 are fixedly connected to the two first connecting rods 11, respectively. Specifically, the connecting rod assembly 1 is arranged between the folding bed frame 2 and the shank board 21 of the folding bed, and the thigh board 22 and the shank board 21 of the folding bed can be rotated and raised by means of the connecting rod assembly 1. Specifically, a point where the second connecting rod 12 is hinged with the first connecting rod 11 is close to the shank board 21 side of the folding bed, and points where the first linking rod 13 is fixed to the two first connecting rods 11 are close to the folding bed frame 2 side to fully guarantee the spatial distance of a stroke of a first driving device pushing a first push rod 32 of the first linking rod 13 and to increase the initial included angle between the first driving device 3 and the shank board 21 in the initial state to enable the pushing to be more labor-saving.

Specifically, the connecting rod assembly 1 further comprises a first guide rail 14, wherein the first guide rail 14 is fixedly connected to the back face of the shank board 21 and is provided with a first guide slot 141 which is a linear slot. In an embodiment of the present invention, the first guide rail 14 comprises a fixing face and a guide face that are perpendicular to each other, wherein the fixing face is fixedly connected to the back face of the shank board 21, the first guide slot 141 is arranged in the guide face, and the extension direction of the first guide slot 141 is parallel to the side of the shank board 21.

Specifically, the connecting rod assembly 1 further comprises a first sliding piece 15, wherein the first sliding piece 15 is connected to one end of the first connecting rod 11 and slides in the extension direction of the first guide slot 141. In an embodiment of the present invention, the first sliding piece 15 comprises a rolling wheel 151 and a fastener 152, wherein the fastener 152 passes through the first guide slot 141 and the rolling wheel 151 and is fixedly connected to one end of the first connecting rod 11, and the fastener 152 can slide in the first guide slot in the extension direction of the first guide slot 141. The first sliding piece 15 may also play a supporting role.

In some embodiments, the connecting rod assembly 1 further comprises a first reinforcing rib 16, wherein one end of the first reinforcing rib 16 is connected to the first connecting rod 11, the other end of the first reinforcing rib 16 is connected to the first linking rod 13, and the first connecting rod 11, the first reinforcing rib 16 and the first linking rod 13 form a triangular structure. The first reinforcing rib 16 is used for increasing the structural strength of the connecting rod assembly 1.

Specifically, the overall thickness of the connecting rod assembly 1 after the connecting rod assembly is folded is less than the frame thickness of the folding bed frame 2, and the frame thickness of the folding bed frame 2 is less than 85 mm. Specifically, the overall thickness of the connecting rod assembly 1 after the connecting rod assembly is fully folded is very small, and when used on a folding bed, the connecting rod assembly 1 can be fully received within the folding bed frame such that the thickness of the folding bed can be made thinner and lighter in weight.

The connecting rod assembly has the function of supporting and adjusting the thigh board 22 and the shank board 21, and the first driving device drives the connecting rod assembly to drive the thigh board and the shank board to rotate upwards relative to a seat board and a bed frame to adjust and raise the legs.

FIGS. 4-6 show a folding bed of the present application. The folding bed comprises the connecting rod assembly 1 described above, and further comprises a folding bed frame 2, a thigh board 22, a shank board 21 and a first driving device 3, wherein the thigh board 22 is rotatably connected to the shank board 21, the first driving device 3 comprises a first motor 31 and a first push rod 32, the first motor 31 is used for driving the first push rod 32, the first push rod 32 is used for pushing the first linking rod 13, and the first driving device 3 is used for driving the first linking rod 13 to drive the shank board 21 and the thigh board 22 to move.

Specifically, a first connecting piece 33 is arranged between the first push rod 32 and the first linking rod 13, one end of the first connecting piece 33 is rotatably connected to the first push rod 32, and the other end of the first connecting piece 33 is connected to the first linking rod 13.

Specifically, the inner side frame of the folding bed frame 2 is rotatably connected to the other end of the first connecting rod 11 by an assembly 4, the assembly 4 comprises a hollow sleeve 41 and a screw 42, the hollow sleeve 41 is fixedly connected to the folding bed frame 2, the first connecting rod 11 hollowly sleeves the hollow sleeve 41, and the screw 42 is in matched connection to the hollow sleeve 41. In this embodiment, the interior of the hollow sleeve 41 is provided with an internal thread matched with an external thread of the screw 42. In some embodiments, the hollow sleeve 41 can also be fixedly mounted to the folding bed frame 2 by means of a fixing piece 43, the fixing piece 43 is welded to the side frame of the folding bed frame 2, an end of the first connecting rod 11 close to the folding bed frame is provided with an assembly hole, and the screw 42 passes through the assembly hole and is locked with the hollow sleeve 41 such that the first connecting rod 11 is rotatably connected to the hollow sleeve 41. In some other embodiments, a washer 44 is additionally arranged between the screw 42 and the first connecting rod 11. The present invention adopts the assembly 4 with the hollow sleeve 41 structure, so that the strength of connection between the first connecting rod 11 and the folding bed frame 2 can be greatly increased.

Specifically, as shown in FIG. 1 , an end of the thigh board 22 close to the shank board 21 is provided with a linkage piece 5, one end of the linkage piece 5 is rotatably connected to the second connecting rod 12, and the other end of the linkage piece 5 is fixedly connected to the thigh board 22. The second connecting rod 12 is rotatably connected to the thigh board 22 by means of the linkage piece 5, in an embodiment of the present invention, the linkage piece 5 comprises a rectangular piece and an L-shaped piece that are integrally formed, the L-shaped piece is perpendicular to the rectangular piece, the rectangular piece is fixed to the back face of the thigh board 22, and the short side of the L-shaped piece is rotatably connected to the second connecting rod 12.

Specifically, the folding bed further comprises a seat board 23 and a back board 24, the folding bed frame 2 comprises a back frame 25 and a leg frame 26 that are hinged, the back board 24 is arranged on the back frame 25, and the seat board 23, the thigh board 22 and the shank board 21 are hinged in sequence and arranged on the leg frame 26. The seat board 23 is fixed at an end of the leg frame close to the back frame 25, the seat board 23 and the thigh board 22 are hinged via a hinge, and the thigh board 22 and the shank board 21 are hinged via a hinge. As shown in FIG. 4 , in some embodiments, the back board 24 comprises a first back board 241 and a second back board 242, wherein the second back board 242 is fixed to a side of the back frame 25 close to the leg frame 26, and the first back board 241 and the second back board 242 are hinged via a hinge. A hinge assembly 6 and a second driving device 7 are arranged between the first back board 241 and the back frame 25, and the second driving device 7 drives the first back board 241 to rotate relative to the back frame 25 via the hinge assembly 6.

As shown in FIG. 5 , specifically, the hinge assembly 6 comprises a second linking rod 62 and two back brackets 61, wherein one end of the back bracket 61 is slidably connected to the first back board 241 of the folding bed, the other end of the back bracket 61 is rotatably connected to the back frame 25, two ends of the second linking rod 62 are fixedly connected to the two back brackets 61, respectively, and the second linking rod 62 is connected to the second driving device 7 and drives the first back board 241 to rotate relative to the back frame 25. Specifically, points where the second linking rod 62 is fixed to the two back brackets 61 are close to the back frame 25 side. The second linking rod 62 and the two back brackets 61 form a stable bracket structure. In addition, the second linking rod 62 is connected to the second driving device 7, so that the initial included angle between the second driving device 7 and the first back board 241 in the initial state can be increased, thereby enabling the pushing to be more labor-saving and the folding bed to be overall designed to be thinner.

In some embodiments, the hinge assembly 6 further comprises a second reinforcing rib 34, wherein one end of the second reinforcing rib 34 is connected to the back bracket 61, the other end of the second reinforcing rib 34 is connected to the second linking rod 62, and the back bracket 61, the second reinforcing rib 34 and the second linking rod 62 form a triangular structure. The second reinforcing rib 34 here is used for increasing the structural strength of the hinge assembly 6. As shown in FIG. 6 , in an embodiment of the present invention, the hinge assembly 6 further comprises a second guide rail 63, wherein one end of the second guide rail 63 is slidably connected to one end of the back bracket 61, and the other end of the second guide rail 63 is fixedly connected to the first back board 241 of the folding bed. One end of the back bracket 61 is slidably connected to the second guide rail 63 by means of a second sliding piece 64. The other end of the back bracket 61 is rotatably connected to the folding bed frame 2 by means of the aforementioned assembly 4. The present invention adopts the assembly 4 to greatly increase the strength of the connection between the back bracket 61 and the folding bed frame 2.

Specifically, as shown in FIGS. 1 and 6 , in an embodiment of the present invention, the second sliding piece 64 has the same structure as the first sliding piece 15, and the second guide rail 63 has the same structure as the first guide rail 14.

That is, the second guide rail 63 is provided with a second guide slot 631, the second guide slot 631 is a linear slot, and the second sliding piece 64 is connected to one end of the back bracket 61 and slides in the extension direction of the second guide slot 631.

Specifically, the overall thickness of the hinge assembly 6 after the hinge assembly is folded is less than the frame thickness of the folding bed frame 2, and the frame thickness of the folding bed frame 2 is less than 85 mm. Specifically, the overall thickness of the hinge assembly 6 after the connecting rod assembly is fully folded is very small, and when used on a folding bed, the hinge assembly 6 can be fully received within the frame of the folding bed such that the thickness of the folding bed can be made thinner and lighter in weight.

In an embodiment of the present invention, the hinge assembly has the function of supporting and adjusting the back board, and the second driving device 7 drives the hinge assembly to drive the back board to rotate upwards relative to the folding bed frame so as to adjust and raise the back. In this embodiment, the second driving device 7 comprises a second motor 71 and a second push rod 72, wherein one end of the second motor 71 is connected to the head end of the folding bed frame 2, the other end of the second motor 71 is connected to the second push rod 72, the second push rod 72 is rotatably connected to a second connecting piece 73 that is arranged between the second push rod 72 and the second linking rod 62, one end of the second connecting piece 73 is rotatably connected to the second push rod 72, and the other end of the second connecting piece 73 is connected to the second linking rod 62. The second motor 71 is used for driving the second push rod 72, and the second push rod 72 is used for pushing the second linking rod 62 to drive the back board 24 to rotate relative to the folding bed frame 2. In this embodiment, the second driving device 7 drives the second linking rod 62 to do upward rotation motion or downward rotation motion via the second connecting piece 73 so as to enable the first back board 241 to be folded relative to the second back board 242.

When the second driving device 7 in this embodiment acts, the second linking rod 62 is raised via the second connecting piece 73 to drive the back brackets 61 to act, that is, one end of the back bracket 61 moves forward along the second guide rail 63, and the other end of the back bracket 61 rotates relative to the folding bed frame 2 via the assembly 4, thereby completing the angle adjustment of the back board 24. When the first motor 31 drives the first push rod 32, the first linking rod 13 is driven by the first connecting piece 33 to rotate and be raised to drive the first connecting rods 11 to act, the second connecting rods 12 act under the action of the first connecting rods 11, that is, one end of the first connecting rod 11 rotates relative to the folding bed frame 2 via the assembly 4, the other end of the first connecting rod 11 moves forward along the first guide rail 14 via the first sliding piece 15 to drive the shank board 21 to be raised, and since the first guide rail 14 is fixed to the shank board 21, one end of the second connecting rod 12 rotates relative to the first connecting rod 11, and the other end of the second connecting rod 12 rotates relative to the thigh board 22 via the linkage piece 5.

Both the connecting rod assembly and the hinge assembly in this embodiment are irregular pieces, in order to ensure that the folding bed can be used on the ground with zero clearance, neither the distance between the lowest point when the hinge assembly 6 and the connecting rod assembly 1 move and the ground nor the distance between the lowest point of the hinge assembly 6 and the ground is less than the distance between the folding bed frame 2 and the ground, so that the connecting rod assembly 1 and the hinge assembly 6 can be hidden in the folding bed frame 2 to reduce the overall thickness of the folding bed frame 2 to enable the bed body to be thinner, and a specific structure is shown in FIG. 9 .

Specifically, in some other embodiments, as shown in FIG. 7 , in order to prevent bending deformation of the boards of the folding bed, a plurality of metal pieces 8 can be arranged on the lower surfaces of the boards, and the metal piece 8 is of a strip-shaped reinforcing structure. For example, two ends of the lower surface of the first back board 241 are each provided with a strip-shaped metal piece 8, one end of a hinge at the connection of the first back board 241 and the second back board 242 is fixed to the metal piece 8, and the other end of the hinge is fixed to the second back board 242, so that the first back board 241 can be folded relative to the second back board 242; two ends of the lower surface of the shank board 21 are also each fixedly provided with a strip-shaped metal piece 8, one end of a hinge through which the shank board 21 is hinged with the thigh board 22 is fixed to the metal piece 8 of the shank board 21, and the other end of the hinge is fixed to the thigh board 22, so that the shank board 21 can be folded relative to the thigh board 22. The longitudinal length of the metal piece 8 in this embodiment is slightly less than the longitudinal width of the folding bed frame 2.

Specifically, in some other embodiments, as shown in FIG. 8 , in order to prevent bending deformation of the boards and to improve the support strength of the folding bed frame 2, the bed head end and the bed foot end of the folding bed frame 2 are each additionally provided with a plurality of supporting pieces 9, in some embodiments, the bed head end and the bed foot end of the folding bed frame 2 are each additionally provided with two supporting pieces 9, the upper surface of the supporting piece is flush with the surface of the side frame of the folding bed frame 2, the bed head frame referred to in this embodiment is the frame for fixing the second motor 71, and the bed foot frame is the frame for fixing the first motor 31.

The connecting rod assembly, the hinge assembly, the first driving device and the second driving device of the present invention can all be hidden in the folding bed frame, so that the overall structure of the folding bed is more concise and requirements of consumers on the appearance of a bed can be better met, at the same time, the bed can be used on the ground with zero clearance, and the connecting rod assembly of the present invention is simple in structure and can enable the overall thickness of the folding bed to be reduced from 120-200 mm in the prior art to less than 85 mm. The connecting rod assembly is additionally provided with the second connecting rods, so that the shortcoming of the inadequate support structures of the existing folding bed is solved, the structural strength of the folding bed is greatly enhanced, and the service life of the folding bed is prolonged. The folding bed is simple in structure and occupies less area compared to the prior art after being folded, so that the transportation cost is greatly reduced. The folding bed of the present invention can be not provided with bed legs to be directly used on the ground with zero clearance, or can be provided with bed legs to be used off the ground.

The above embodiments are preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can also be made, and these improvements and modifications can also be regarded as falling within the protection scope of the present invention. 

1. A folding bed, comprising a connecting rod assembly (1), a folding bed frame (2), a thigh board (22), a shank board (21) and a first driving device (3), wherein the thigh board (22) is rotatably connected to the shank board (21); the connecting rod assembly (1) comprises two first connecting rods (11), two second connecting rods (12) and a first linking rod (13), wherein one end of the first connecting rod (11) is slidably connected to the shank board (21) of the folding bed, and another end of the first connecting rod (11) is rotatably connected to the folding bed frame (2); one end of the second connecting rod (12) is rotatably connected to the first connecting rod (11), the other end of the second connecting rod (12) is used for driving the thigh board (22) of the folding bed to rotate, and two ends of the first linking rod (13) are fixedly connected to the two first connecting rods (11), respectively; the first driving device (3) comprises a first motor (31) and a first push rod (32), wherein the first motor (31) is used for driving the first push rod (32), and the first push rod (32) is used for pushing the first linking rod (13) so as to drive the shank board (21) and the thigh board (22) to move.
 2. The folding bed according to claim 1, characterized in that a point where the second connecting rod (12) is rotatably connected to the first connecting rod (11) is close to the shank board (21) side of the folding bed, and points where the first linking rod (13) is fixed to the two first connecting rods (11) are close to the folding bed frame (2) side.
 3. The folding bed according to claim 1, characterized by further comprising a first guide rail (14), wherein the first guide rail (14) is fixedly connected to a back face of the shank board (21), and is provided with a first guide slot (141) which is a linear slot.
 4. The folding bed according to claim 3, characterized by further comprising a first sliding piece (15), wherein the first sliding piece (15) is connected to one end of the first connecting rod (11) and can slide in an extension direction of the first guide slot (141).
 5. The folding bed according to claim 1, characterized in that an overall thickness of the connecting rod assembly (1) after the connecting rod assembly is folded is less than a frame thickness of the folding bed frame (2), and the frame thickness of the folding bed frame (2) is less than 85 mm.
 6. The folding bed according to claim 1, characterized in that the first driving device (3) further comprises a first connecting piece (33), wherein one end of the first connecting piece (33) is rotatably connected to the first push rod (32), and another end of the first connecting piece (33) is connected to the first linking rod (13).
 7. The folding bed according to claim 1, characterized in that an inner side frame of the folding bed frame (2) is rotatably connected to the first connecting rod (11) by means of an assembly (4), the assembly (4) comprises a hollow sleeve (41) and a screw (42), the hollow sleeve (41) is fixedly connected to the folding bed frame (2), the first connecting rod (11) hollowly sleeves the hollow sleeve (41), and the screw (42) is in matched connection to the hollow sleeve (41).
 8. The folding bed according to claim 1, characterized in that an end of the thigh board (22) close to the shank board (21) is provided with a linkage piece (5), one end of the linkage piece (5) is rotatably connected to the second connecting rod (12), and another end of the linkage piece (5) is fixedly connected to the thigh board (22).
 9. The folding bed according to claim 1, characterized by further comprising a seat board (23) and a back board (24), wherein the folding bed frame (2) comprises a back frame (25) and a leg frame (26) that are hinged to each other, the back board (24) is arranged on the back frame (25), and the seat board (23), the thigh board (22) and the shank board (21) are hinged in sequence and arranged on the leg frame (26); a hinge assembly (6) and a second driving device (7) are arranged between the back board (24) and the back frame (25), and the second driving device (7) drives the back board (24) to rotate relative to the back frame (25) via the hinge assembly (6).
 10. The folding bed according to claim 9, characterized in that the hinge assembly (6) comprises a second linking rod (62) and two back brackets (61), wherein one end of the back bracket (61) is slidably connected to the back board (24) of the folding bed, another end of the back bracket (61) is rotatably connected to the folding bed frame (2), two ends of the second linking rod (62) are fixedly connected to the two back brackets (61), respectively, and the second linking rod (62) is connected to the second driving device (7) and drives the back board (24) to rotate relative to the folding bed frame (2).
 11. The folding bed according to claim 10, characterized in that points where the second linking rod (62) is fixed to the two back brackets (61) are close to the folding bed frame (2) side.
 12. The folding bed according to claim 10, characterized in that the hinge assembly (6) further comprises a second guide rail (63), wherein the second guide rail (63) is fixedly connected to a back face of the back board (24), and is provided with a second guide slot (631) which is a linear slot.
 13. The folding bed according to claim 12, characterized in that the hinge assembly (6) further comprises a second sliding piece (64), wherein the second sliding piece (64) is connected to one end of the back bracket (61) and can slide in an extension direction of the second guide slot (631).
 14. The folding bed according to claim 10, characterized in that an overall thickness of the hinge assembly (6) after the hinge assembly is folded is less than a frame thickness of the folding bed frame (2), and the frame thickness of the folding bed frame (2) is less than 85 mm.
 15. The folding bed according to claim 10, characterized by further comprising a second driving device (7), wherein the second driving device (7) comprises a second motor (71) and a second push rod (72), the second motor (71) is fixed to the folding bed frame (2) and is used for driving the second push rod (72), the second push rod (72) is used for pushing the second linking rod (62) so as to drive the back board (24) to rotate relative to the folding bed frame (2).
 16. The folding bed according to claim 15, characterized in that a second connecting piece (73) is arranged between the second push rod (72) and the second linking rod (62), one end of the second connecting piece (73) is rotatably connected to the second push rod (72), and another end of the second connecting piece (73) is connected to the second linking rod (62).
 17. The folding bed according to claim 15, characterized in that an inner side frame of the folding bed frame (2) is rotatably connected to the back bracket (61) by means of an assembly (4), the assembly (4) comprises a hollow sleeve (41) and a screw (42), the hollow sleeve (41) is fixedly connected to the folding bed frame (2), the back bracket (61) hollowly sleeves the hollow sleeve (41), and the screw (42) is in matched connection to the hollow sleeve (41).
 18. The folding bed according to claim 15, characterized in that the back board (24) comprises a first back board (241) and a second back board (242) that are hinged to each other, wherein the first back board (241) is slidably connected to the back bracket (61), and the second back board (242) is fixed to an end of the back frame (25) close to the leg frame (26). 